An exasperated Jose Mourinho suggested the VAR official must have been "having a tea" after a heavy tackle from Andy Robertson went unpunished in Liverpool's 1-0 win over Tottenham on Saturday.
After taking a poor touch deep in Spurs territory during the second half, a stretching Robertson appeared to catch Spurs debutant Japhet Tanganga firmly on the shin with his studs.
However, the Liverpool left-back was not even booked for the incident and Mourinho was less than impressed.
After hailing Jurgen Klopp's side, who are 16 points clear at the top of the Premier League after a 20th win from 21 games, the Spurs head coach suggested his team had been hard done by, comparing Robertson's challenge to the incident that saw Son Heung-min dismissed against Chelsea following a VAR review.
"They are so, so good and so, so strong in every area," said Mourinho of Liverpool in an interview with Sky Sports. "On top of that, they are lucky.
"Because they were lucky – they could perfectly concede a goal, they could perfectly finish the game with 10 because the VAR at the time they were having a [cup of] tea and they didn't watch Robertson for a red card.
"Compare that with Son [against Chelsea], when Son got a red card."
Mourinho also felt Liverpool were wrongly awarded a throw-in prior to Roberto Firmino scoring the only goal of the game, but he was proud of Tottenham's efforts in the absence of injured talisman Harry Kane, who is set to be out until at least April.
"I think I have only reasons to be sad with the result, but I have only reasons to be happy and proud of what the boys did and tried to do with the situation we had," he added.
"I think we deserved more from this game.
"With the throw-in [before Firmino's goal], that should be a throw-in in our favour, so it's a bit frustrating. I think the refs did a very good job, but unfortunately the assistant on the opposite side of us didn't see that throw-in."
In an interview with the BBC, Mourinho said: "This is football. Sometimes you get more than you deserve, sometimes you get less. I think this was one of the occasions when we got nothing when we deserved so much to get something.
"It was probably the best team in the world in the maximum of its potential against a team in a difficult moment, lots of injuries, important injuries, a difficult season, and I think the boys competed in a fantastic way. We were just unlucky not to score."